733 research outputs found
Local properties of patterned vegetation: quantifying endogenous and exogenous effects
Dryland ecosystems commonly exhibit periodic bands of vegetation, thought to
form due to competition between individual plants for heterogeneously
distributed water. In this paper, we develop a Fourier method for locally
identifying the pattern wavenumber and orientation, and apply it to aerial
images from a region of vegetation patterning near Fort Stockton, Texas. We
find that the local pattern wavelength and orientation are typically coherent,
but exhibit both rapid and gradual variation driven by changes in hillslope
gradient and orientation, the potential for water accumulation, or soil type.
Endogenous pattern dynamics, when simulated for spatially homogeneous
topographic and vegetation conditions, predict pattern properties that are much
less variable than the orientation and wavelength observed in natural systems.
Our local pattern analysis, combined with ancillary datasets describing soil
and topographic variation, highlights a largely unexplored correlation between
soil depth, pattern coherence, vegetation cover and pattern wavelength. It
also, surprisingly, suggests that downslope accumulation of water may play a
role in changing vegetation pattern properties
Performance improvement technology for building a sustainable OER initiative in an academic library
In keeping with its land grant mission, a university campus library partnered with several OER advocacy efforts on both national and state levels to promote the creation and use of OER at the university. While the program had some initial success in inspiring faculty to create and use OER in their courses, the effort proved difficult to sustain. This paper presents the application of the Performance Improvement/HPT model to an Open Educational Resources (OER) initiative in a university library. This paper focuses specifically on three phases of the process: organizational analysis, environmental analysis, and gap analysis We share results of that application and discuss how the HPT model might effectively be applied to other similar programs.Peer reviewedLibraryEducational Technolog
Why is the Arkavathy River drying? A multiple-hypothesis approach in a data-scarce region
Water planning decisions are only as good as our ability to explain historical trends and make reasonable predictions of future water availability. But predicting water availability can be a challenge in rapidly growing regions, where human modifications of land and waterscapes are changing the hydrologic system. Yet, many regions of the world lack the long-term hydrologic monitoring records needed to understand past changes and predict future trends. We investigated this “predictions under change” problem in the data-scarce Thippagondanahalli (TG Halli) catchment of the Arkavathy sub-basin in southern India. Inflows into TG Halli reservoir have declined sharply since the 1970s. The causes of the drying are poorly understood, resulting in
misdirected or counter-productive management responses.
Five plausible hypotheses that could explain the decline
were tested using data from field surveys and secondary
sources: (1) changes in rainfall amount, seasonality and intensity; (2) increases in temperature; (3) groundwater extraction; (4) expansion of eucalyptus plantations; and (5) fragmentation of the river channel. Our results suggest that groundwater pumping, expansion of eucalyptus plantations and, to a lesser extent, channel fragmentation are much more likely to have caused the decline in surface flows in the TG Halli catchment than changing climate
Robot-assisted measurement for hydrologic understanding in data sparse regions
This article describes the field application of small, low-cost robots for remote surface data collection and an automated workflow to support water balance computations and hydrologic understanding where water availability data is sparse. Current elevation measurement approaches,
such as manual surveying and LiDAR, are costly and infrequent, leading to potential inefficiencies for
quantifying the dynamic hydrologic storage capacity of the land surface over large areas. Experiments to evaluate a team of two different robots, including an unmanned aerial vehicle (UAV) and an unmanned surface vehicle (USV), to collect hydrologic surface data utilizing sonar and visual sensors were conducted at three different field sites within the Arkavathy Basin river network located near
Bangalore in Karnataka, South India. Visual sensors were used on the UAV to capture high resolution imagery for topographic characterization, and sonar sensors were deployed on the USV to capture bathymetric readings; the data streams were fused in an automated workflow to determine the storage capacity of agricultural reservoirs (also known as “tanks”) at the three field sites. This study suggests: (i) this robot-assisted methodology is low-cost and suitable for novice users, and (ii) storage capacity data collected at previously unmapped locations revealed strong power-type relationships between surface area, stage, and storage volume, which can be incorporated into modeling of landscape-scale hydrology. This methodology is of importance to water researchers and practitioners because it produces local, high-resolution representations of bathymetry and topography and enables water balance computations at small-watershed scales, which offer insight into the present-day dynamics of a strongly human impacted watershed
A mixed-methods investigation into the acceptability, usability and perceived effectiveness of active and passive virtual reality scenarios in managing pain under experimental conditions
Burns patients often suffer excruciating pain during clinical procedures, even with analgesia. Virtual Reality as an adjunct to pharmacological therapy has proved promising in the management of burn pain. More evidence is needed regarding specific forms of Virtual Reality. This mixed-method study examined the impact of active and passive Virtual Reality scenarios in experimental conditions, gathering data relating to user experience, acceptability and effectiveness in managing pain. Four scenarios were developed or selected following a consultative workshop with burns survivors and clinicians. Each was trialled using a cold pressor test with 15 University students. Data were gathered regarding pain threshold and tolerance at baseline and during each exposure. Short interviews were conducted afterwards. The two active scenarios were ranked highest and significantly extended participants pain threshold and tolerance times compared to passive and baseline conditions. Passive scenarios offered little distraction and relief from pain. Active scenarios were perceived to be engaging, challenging, distracting and immersive. They reduced subjective awareness of pain, though suggestions were made for further improvements. Results suggested that active Virtual Reality was acceptable and enjoyable as a means of helping to control experimental pain. Following suggested improvements, scenarios should now be tested in the clinical environment
Identifying culturally appropriate strategies for coronary heart disease secondary prevention in a regional Aboriginal Medical Service
Aboriginal Australians experience high rates of coronary heart disease (CHD) at an early age, highlighting the importance of effective secondary prevention. This study employed a two-stage process to evaluate CHD management in a regional Aboriginal Medical Service. Stage 1 involved an audit of 94 medical records of clients with documented CHD using the Audit and Best Practice in Chronic Disease approach to health service quality improvement. Results from the audit informed themes for focus group discussions with Aboriginal Medical Service clients (n = 6) and staff (n = 6) to ascertain barriers and facilitators to CHD management. The audit identified that chronic disease management was the focus of appointments more frequently than in national data (P < 0.05), with brief interventions for lifestyle modification occurring at similar or greater frequency. However, referrals to follow-up support services for secondary prevention were lower (P < 0.05). Focus groups identified psychosocial factors, systemic shortcomings, suboptimal medication use and variable awareness of CHD signs and symptoms as barriers to CHD management, whereas family support and culturally appropriate education promoted health care. To optimise CHD secondary prevention for Aboriginal people, health services require adequate resources to achieve best-practice systems of follow up. Routinely engaging clients is required to ensure services meet diverse community needs
Length of exposure to high post-rigor temperatures affects the tenderisation of the beef M. longissmus dorsi
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